What I did with my wife was if there was any communication that went on :
1. I owned anything she called me on that I DID do wrong. It disarmed her immediately 2. I followed through with "THAT is past mistakes. Right NOW what am I doing wrong and what are YOU doing wrong?" 3. I finished up with the confrontation script - "YOU are HURTING ME, you are HURTING our FAMILY, you are HURTING yoru FRIENDS...etc
If he complains about something legitimiate then own it, but don't fall at his feet apologizing, he's mounting another woman behind your back.. you need to preserve your dignity or he is gonna walk all over you.
My wife was bringign mistakes I made TEN YEARS prior to the affair that I had NOT repeated... I was quick to ask her "do you have anything recent? Because you reek of cheat RIGHT NOW so your ten year old complaints don't really carry a lot of credibility on this side of the fence..."